Brake mechanism



19, 1941. c. L. EKSERGIAN Em. ,2 3 2 8 BRAKE MECHANISM Filed March 1, 1940 I 2 Sheets-Sheet l I N V EN TOR v CZzroZzzs L,Z7i5er zan/ J2me hjl. 60% ea A TTORNE Y Patented Aug. 19, 1941 BRAKE MECHANISM Carolus L. Eksergian and Joseph H. Coombes,

Detroit, Mich., asslgnors to Budd Wheel Company, Philadelphia, Pa., a corporation of Pennsylvania I Application March 1, 1940, Serial No. 321,688

I 13 Claims. The present invention relates to brakes.

' The side frames may be connected by the cross More specifically, the invention relates to supporting the weight of the frame carrying one part of the brake mechanism by a relatively weak or low rate resilient means, having suflicient resistance to support said weight when the brake is not acting, but insufliclcnt to overcome the thrust produced during braking.

The invention, which is particularly applicable 7 to brakes of the so-called disk type, wherein the brake cylinders and brake'shoes are carried by a yoke or C-irame, further contemplates providing relatively strong or high rate resilient means, such as stiff bumpers for example, to cooperate with the frame so that they will carry the thrust during the braking periods.

while solid rubber buffers assume the thrust of.

brakin both the helical springs and the buffers being carried by the equalizer bars, which afford a steadier support than would the truck frame itself, as heretofore often used.

Other objects and featureslof the invention will be evident from the present specificationdescriptive of a preferred embodiment of the same, and the drawings accompanying it and forming a part thereof.

In said drawings:

Fig. l is a fragmentary plan view showing approximately one-half of a wheel truck, including brake mechanism eimbodying the invention Fig. 2 is a sectional elevation corresponding to Fig. l, the section beingmade on the plane indicated by the line 2-2 thereof, the brake cylinders and certainparts operated thereby being the equalizer bars 2 and 3 by helical springs 23' interposed between said bars and the side mem-.

bers of the frame i, suitable supports 3! being .mounted on the equalizer bars and having recesses 32 therein to receive and retain the lower ends of the said springs, while corresponding members 33 are provided on the side frames, to

receive and retain the upper ends of the springs.

members 25 constituting the transom.

The truck carries the axles 4, having thereon the wheels 5 and brake rings Ii, said rings being secured to the hub flanges 29 by bolts or the like 30. The ends of each axle 4 are mounted in journal boxes 1, mounted in pedestals 21 and 28, carried by the truck frame. The equalizer bars 2 and 3 have their endportions upwardly offset and resting on the journal boxes I (see Figs. 1

and 3). Mounted upon the inner end of each journal box-I, so as to pivot about the axis of the axle t, is the corresponding supporting arm 20 forming part of the O-frame or brake yoke.

Said arms 20 are rigidly attached to the opposite ends of the tubular cross piece 8 which carries part of the brake mechanisms, each of which is here shown as comprising a cylinder H mounted on a lever l0 plvotally held at M on a flange lb of the cross member 8, the short forward arm of said lever Ill being plvotally attached at I8 to a brake shoe I6. Said mechanism further comprises another lever 9 pivotally mounted at it, and pivotally attached at l2 to the piston rod of the cylinder H, the short arm of lever 9 being plvotally secured at ll to a brake shoe it, the said brake shoes being placed on opposite sides of the brake ring 6, so that when the piston is forced out of the cylinder by supplying pressure fluid through the port 26, the brake shoes will be forced against the opposite faces of the ring t.

Each arm 2d has a semi-circular end engaging around the journal box l and cooperating with a strap ii to complete the circle, said strap being secured to the end of the arm 2!! in any suitable way, as by the bolts 22.

As so far described, the brake yoke or C-frame comprising the arms 20 and the cross member t could rotate freely about the journal boxes. In order to prevent such rotation, except for a necessary small range of the'same, rearwardly extending flanges 34 and 35 may be provided at each end of the cross piece 8, as best shown in Fig. 4, and a pin 36 inserted through corresponding alined bores in said flanges, to support pivotally a block or disk 31.

The lower surface of this block may have therein a recess 38, within which is seated the upper end of a relatively weak helical spring 39, the lower end of which is received and retained in a corresponding recess 40, formed in an inward extension ll of the supportlli, which latter has its base 3|a mounted between the equalizer bars .I'and 3. This extension 4| terminates in a fork having the lower arm 42 in which the recess 40 is rib 44 arranged between springs 23 (see Fig. 1)

preferably being provided to stiffen the extension 4|.

The lower arm 42 may carry a yieldable bumper 45, preferably consisting of rubber, vulcanized to a nut 45 which is secured in position by means of the cap screw 41 and lock washer 48, the buffer 45 being of such length that the lower surface of the disk 31 will strike the top thereof shortly before the spring 39 is fully compressed. Another bumper or bufier 49, also consisting of a rubber portion vulcanized to a nut 50, cooperates with the upper surface of the disk 3'! and is secured in the arm 43 by the cap screw 5| and lock washer 52.

The two corresponding supports 3| on opposite sides of the truck frame, carried by theequalizer bars 2 and 3, are suitably braced or strengthened by means of a bar or rod 24 extending across the frame. It will be seen that a pin or bolt 51, having a clevis head 58, passes through 'each pair of equalizer bars 2, 3, and the support 3|, a nut 54 and lock washer 55 being provided to secure these parts together firmly.

A cooperating nut 55 having an eyelet at its ring in service, will act in line with said springs, and be absorbed and cushioned thereby without jarring the pivotal'connections of the yoke to the journal boxes.

The rubber buffers 45 and 49-, when sufllclently compressed, will act as rigid solids, which happens only when the brakes are applied, the torque tially coaxial with the axis of the rotary element, and yieldable supporting means cooperating with said yoke to limit the rotation of the yoke about its pivot, and acting on said yoke end is threaded on each end of the rod 24, and

locked in place by the locknut 53. A pin 59 passes through the clevis and the eyelet in the nut 55 to hold the said equalizer bars from tilt-.

ing or twisting, the pins 59 providing sufilcient pivotal action to prevent binding, and the nuts 55 perm tting adjustment of the effective length of the rod 24.

It may be remarked that the supports 3i serve the double purpose of carrying the springs 23 on the one hand, and the springs 39 and buffers and 49 on the other hand. By carrying these latter on the equalizer bars instead of mounting them on the frame I, the advantage is secured that the springs 39 obviously are much less likely to be disturbed by vertical motion of their supports.

The operation of the invention is as follows:

When it is desired'to apply the brakes, compressed air or the like is admitted to the cylindersll, whereupon the piston and cylinder in each instance will move in opposite directions, separating the rear arms of the levers 9 and Ill. and thereby causing the short forward arms to bring the brake shoes l5 ond l5 against the respective sides of the brake rings 5.

When the brake shoes are thus engaged with the rings, the momentum of the vehicle will cause the brake yoke 8 to pivot about the axis of the axle 4 in one direction or the other, de-

pending upon the direction in which the vehicle is traveling, and such pivotal motion will there-- the center of percussion of the c-frame or yoke.

These springs are relatively weak or low rate, since they need carry only about 350 to 375 pounds each, in the example herein disclosed. By reason of the positioning of these springs in vertical alignment with the center. of percussion of the yoke, the resultant of the inertia movements of the yoke. produced by shocks and jarsubstantially'ifi alinement with the center of percussion thereof.

2. A brake mechanism comprising a rotatable brake ring, a brake shoe cooperating therewith, means for actuating said brake shoe, a yoke supporting said actuating means, said yoke being pivotally supported about an axis substantially coaxial with the axis of the brake ring, and

brake ring, a brake shoe cooperating therewith,'

means for actuating said brake shoe, a yoke supporting said actuating means, said yoke being pivotally supported about an axis substantially coaxial with the axis of the brake ring, and yieldable supporting means cooperating with said yoke to limit the rotation of the yoke about said axis, and acting on said yoke substantially in alinement with the center of percussion being pivotally supported about an axis substantially in alinementcoaxial with the axis of the brake member, and duplex yieldable supporting means cooperating with said yoke to limit the rotation of the yoke about said axis, and acting onsaid yoke substantially in alinement with the center of percussion thereof, said duplex means comprising two independentyieldable devices of materially different degrees of stillness, engageable successively.

5, A brake mechanism comprising a rotary element, means fr ctionally engageable therewith, a yoke supporting said means, said yoke being pivotally supported about an axis substantially coaxial with the axis of the rotary element, and duplex supporting means comprising a yieldable device normally in contact with the yoke and-a second yieldable device arranged to abut against said yoke when the brake is applied, to

limit the rotation of the yoke about its pivot, said first-named yieldable device acting on "sa d yoke substantially in. alinement with the center of percussion thereof.

6. Means for controlling the motion of a pivotally mounted brake yoke about its axis, comprising a relatively weak resilient member normally continually supporting said yoke at a point remote from said axiaand a lender of yieldable material having a relatively great resistance compared to said resilient member, and engageable by said yoke upon substantial pivotal motion'thereof due to brake application.

7. Means for controlling the motion of a pivotally mounted brake yoke about its axis, comprising a relatively weak spring normally continually supporting said yoke at a point remote from said axis, and substantially in line with the center of percussion of the yoke, and a buffer of yieldable material having a relatively great resistance compared to said spring, and

' eng-ag'eable by said yoke upon substantial pivotal motion thereof due to brake application.

8. Means for controlling the motion of a piv-. ot'ally mounted brake yoke about its axis, comprising a pair of relatively weak resilient members normally continually supporting said yoke at spaced points adjacent opposite ends of the yoke and remote from said axis, and a butler of yieldable material having a relatively great resistance compared to said resilient member, and engageable by said yoke upon substantial pivotal mo} tion thereof due to brake application.

9. Meansfor controlling the motion of a pivotally mounted brake yoke about its axis, comprising a pair of relatively weak resilient'members normally continually supporting said yoke at for, said brake mechanism comprising a rotary brake element, a non-rotary brake element for cooperation therewith, a support for said lastnamed element, said support being pivotally mounted about an axis substantially coaxial with the axis of said rotary element, and cushioning means for said support remote from the axis of said rotary element and between the support and the equalizer bars.

11. The combination of a' railway truck having a frame, a wheel and axle assembly and equalizer bars supported thereby, and a brake mechanism therefor, said brake mechanism comprising a rotary brake element, a non-rotary brake element for cooperation therewith, a yoke supporting said last-named element, said yoke being pivotally mounted about an axis substantially coaxial with the axis of said rotary element, spring seating abutments associated with said equalizer bars, springs engaging said abutments and supporting said truck frame from the equalizer bars, said abutments having lateral extensions, and springs supporting said yoke from said lateral extensions.

12. The combination of a railway truck having a wheel and axle assembly and equalizer bars at the opposite sides of the truck supported by said assembly and a brake mechanism therefor, said brake mechanism comprising a rotary brake ele ment, a non-rotary brake element for cooperation therewith, a yoke supporting said last- .named element, said yoke being pivotally mounted about an axis substantially coaxial with the axis of said rotary element, means yieldably supporting said yoke from the equalizer bars, and means transversely connecting the equalizer bars on the opposite sides of the truck in the region of said yieldable supporting means.

13. The combination of a railwaytruck having a wheel and axle assembly and equalizer bars supported thereby, and a brake mechanism there for, said brake mechanism comprising rotary brake elements one adjacent to and rotatable with each wheel of said wheel and axle assem bly, a non-rotary brake element for cooperation with each rotary brake element and actuating means therefor including a brake cylinder, a

rigid yoke support for said non-rotary brake elements and their actuating means, said yoke sup port being pivotally carried, at the opposite sides of the truck, from the wheel and axle assembly,

and cushioning means for said support remote from the axis of said assembly and between said support and the equalizer bars.

'CAROLUS L. EKSERGIAN.

JOSEPH COOMBES. 

